export declare const MAX_REF_DEPTH = 10;
export interface ValidationResult {
    file: string;
    kind: 'definition' | 'fragment' | 'invalid';
    errors: string[];
    warnings: string[];
}
/** Filesystem operations required by file-path-aware validators. */
export interface FileSystem {
    existsSync(path: string): boolean;
    readFileSync(path: string): string;
}
export declare function err(r: ValidationResult, msg: string): void;
export declare function validatePathFormat(pathValue: string, ctx: string, r: ValidationResult): void;
export declare function warn(r: ValidationResult, msg: string): void;
export declare function checkUnknownKeys(obj: Record<string, unknown>, validKeys: Set<string>, ctx: string, r: ValidationResult): void;